Safety Measurement System

Measure vs. Percentile

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. Expand for more information.

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure only considers individual performance based on 24 months of data, with a measure of 0 indicating best performance. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. The graph below shows how the carrier’s measure correlates with its percentile rank over a selected period of time.

Measure

Percentile

Measure	Percentile
0	0
0.17	1
0.32	2
0.45	3
0.56	4
0.67	5
0.78	6
0.87	7
0.96	8
1.04	9
1.12	10
1.19	11
1.27	12
1.35	13
1.42	14
1.49	15
1.56	16
1.63	17
1.70	18
1.77	19
1.82	20
1.88	21
1.94	22
2.01	23
2.07	24
2.14	25
2.20	26
2.26	27
2.32	28
2.38	29
2.44	30
2.51	31
2.57	32
2.63	33
2.68	34
2.75	35
2.82	36
2.88	37
2.95	38
3.01	39
3.09	40
3.14	41
3.20	42
3.27	43
3.34	44
3.40	45
3.47	46
3.52	47
3.59	48
3.66	49
3.74	50
3.81	51
3.88	52
3.95	53
4.02	54
4.09	55
4.17	56
4.24	57
4.33	58
4.40	59
4.49	60
4.56	61
4.64	62
4.72	63
4.81	64
4.90	65
4.98	66
5.06	67
5.14	68
5.23	69
5.33	70
5.42	71
5.52	72
5.62	73
5.73	74
5.85	75
5.97	76
6.11	77
6.24	78
6.39	79
6.54	80
6.70	81
6.87	82
7.03	83
7.19	84
7.35	85
7.54	86
7.77	87
7.98	88
8.25	89
8.50	90
8.78	91
9.08	92
9.43	93
9.83	94
10.29	95
10.84	96
11.55	97
12.59	98
14.29	99
23.65	100